1. Just say you have a U21 5* player that trains 40/80/120, and you get him to 6* and he trains at 30/60/90 and then to 7* he trains 20/40/60. then the next season begins and the player is back at 6* so he will train at 30/60/90 again unless he moves into the next training age bracket at 22.
So basically the answer to your question is the player will train at 10% as you mentioned.
2. It's just an example to non-token buyers on how many greens is possible to earn a season if you save them. It's not a suggestion to play these friendlies, its a option.
thanks for the reply, so basically the training is associated to the stars not from where you are starting, thus no point on pushing a player further like 7* or 8* bcz next season he will not be a fast trainer anyway